Method for evaluating mesenchymal stem cell activity, method for culturing mesenchymal stem cells, method for producing therapeutic agent for liver dysfunction, and therapeutic agent for liver dysfunction

Abstract

A method for evaluating the activity level of mesenchymal stem cells, and a method for culturing mesenchymal stem cells using the evaluation method in the field of culturing mesenchymal stem cells for regenerative medicine, and further, a method for producing a therapeutic agent for liver dysfunction and a therapeutic agent for liver dysfunction. This method for evaluating mesenchymal stem cell activity has an assay step for assaying the amount of adenylate kinase 4 (AK4) in the mesenchymal stem cells; and a determination step for determining the activity level of the mesenchymal stem cells from the assayed amount of adenylate kinase 4.

The invention claimed is: 
     
       1. A method of culturing mesenchymal stem cells comprising the steps of:
 isolating mesenchymal stem cells from a subject fluid containing mesenchymal stem cells; 
 culturing the isolated mesenchymal stem cells; 
 sampling a part of the cultured mesenchymal stem cells; 
 assaying the amount of adenylate kinase 4 in the sampled mesenchymal stem cells; and 
 subculturing the assayed sampled mesenchymal stem cells if the assayed amount of adenylate kinase 4 is equal to or higher than a threshold α which is greater than the assayed expression of adenylate kinase 4 when the mesenchymal stem cells are cultured under conditions at 20% oxygen. 
 
     
     
       2. The method of  claim 1 , wherein the subject fluid is a bone marrow aspirate, umbilical cord blood or peripheral blood. 
     
     
       3. The method of  claim 1 , wherein the culturing step comprises dividing the mesenchymal stem cells into plural groups and culturing the plural groups and the sampling step comprises sampling a part of each of the plural groups of mesenchymal stem cells. 
     
     
       4. The method of  claim 1 , wherein the sampled group of mesenchymal stem cells is not subcultured in the subculturing step if the assayed amount of adenylate kinase 4 is lower than the threshold α. 
     
     
       5. The method of  claim 1 , wherein the sampled mesenchymal stem cells are used as a therapeutic agent in the subculturing step if the assayed amount of adenylate kinase 4 is equal to or lower than a threshold β which is smaller than the assayed expression of adenylate kinase 4 when the mesenchymal stem cells are cultured under conditions at 1% oxygen. 
     
     
       6. The method of  claim 1 , additionally comprising the steps of:
 sampling a part of the mesenchymal stem cells subcultured in the subculturing step; 
 assaying the amount of adenylate kinase 4 in the sampled subcultured mesenchymal stem cells; 
 subculturing the sampled subcultured mesenchymal stem cells if the amount of adenylate kinase 4 is equal to or higher than the threshold α; and 
 repeating these steps at least one time. 
 
     
     
       7. The method of  claim 6 , wherein the subculturing step comprises dividing the mesenchymal stem cells into plural groups and subculturing the plural groups.